Method of cleansing molds



Patented Diet. 3,

ARTHUR R. PAYNE, OF CLARKSBUBG, WEST VIRGINIA.

METHOD or otnensms MOLDS.

No Drawing.

T 0 all who m, it may concern:

Be it known that I, ARTHUR R. PAYNE, a citizen of the United States, residing at Clarksburg, in the county of Harrison and State of \Vest Virginia, have invented certain new and useful Improvements in Methods of Cleansing Molds, of which the following is a full, clear, and exact description.

One of the objects of my invention is to provide a method of cleansing molds, particularly molds used in glass making, whereby the molds will be thoroughly cleansed without being scratched or otherwise injured, as often occurs in the present practice.

Another purpose of my invention is to greatly reduce the time and labor which is required in scraping and cleaning glass molds by the method heretofore in use.

In the molding of glass articles a scale forms on the iron molds after short service and it is necessary, of course, that this be removed. The method now used is not only slow and laborious but also often subjects the molds to injury. The cleansing oper ation now employed consists in scraping the molds with a hard stone to loosen and remove the scale. slow process and one which must be performed by skilled labor. A further objection to the old method is that the molds are often scratched by the hard stone required in removing the scale, and are thus rendered useless.

I will now describe in detail my improved method which, as has been found in practice, overcomes the above objections, and quickly and thoroughly cleanses the molds.

In place of the mechanical methods heretofore employed for cleansing molds used in the glass making art, I use an electrochemical process for loosening the scale.

The bat-h employed in my process consists of a dilute solution of sulphuric acid, the proportions of which are about one part of acid to twenty five parts of water, though of course the exact proportions may be Varied as desired: and an electrolyte other than a sulphuric acid solution may be employed if preferred. This solution is placed in a tank which may be of wood or other material incapable of setting up an electro-chemical action.

In my process I use the iron molds as the cathode. and these are immersed in the bath in contact with a metal higher in the electro- Obviously this is a very Application filed November 13, 1920. Serial No.423,85 l.

chemical series, such as zinc, which acts as the anode, This constitutes a galvanic cell which produces a flow of current through the electrolyte from the zinc to the iron. The iron is not attacked, but the acid acts on the -anode, which I am assuming to be zinc, and

causes the formation of zinc sulphate and hydrogen gas. The gas is liberated not only at the Zinc anode but also at the iron cathode, and the result is that a gaseous film is formed between the scale and the iron of the mold, thereby loosening the scale so that it may be readily removed.

The process is thus, in effect, both chemical and mechanical, the gas'being produced by a chemical action, which gas then acts as a mechanical force between the iron and scale to loosen the latter. V

The molds are removed after a very few minutes and are then rinsed in a soda solution to remove the acid that might prove harmful when the iron is out of contact with the zinc. I

After being rinsed in the soda solution the molds are wiped dry to remove the soda solution together with the scale that has been loosened.

If after this treatment some of the scale still remains, it is only necessary to rub the mold with a soft stone which will quickly and easily remove the residue. understood that the use of a soft stone does not result in scratching or otherwise injuring the mold.

It is not new, of course, to clean metals by electro-chemical processes and I do not claim such aprocess broadly, but so far as I know it is entirely new to clean metals by.

the process I have discovered and disclosed above; and before my invention the cleansing of molds used in glass making has been I accomplished entirely by mechanical means.

Having fully described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An electro-chemical process of removing scale from iron which consists in immersing the iron in an electrolyte, such as a dilute solution of sulphuric acid, in contact with a metallic plate higher in the electro-chemical series than iron, such as zinc, and causing a gaseous film, of hydrogen to form between the iron and the scale, thereby loosening the scale. v

2. The method of cleansin iron molds which consists in immersing the iron molds the electrodilute solution of sulphuric acid, forming a metallic contact between the molds and the zinc or other metallic plate, and removing the molds and rinsing them in a soda solution.

' 4. The method of used in the glass making art, which consists in immersing the non molds and zinc, or

other metallic plate higher in the electroiron molds and zinc, or

them in a soda solution, cleansing 1ron moldschemical series than iron, in a dilute solu-* tion of sulphuric acid, forming a contact between the molds and the zinc or other metallic plate,"removing the molds andrins' ing them in a soda solution, drying the molds, and'rubbing them with a soft stone 'or equivalent material.

5.- he process of removing scale from iron molds used in glass making, which consists in immersing the iron molds in a solution of sulphuric acid, in contact with a zinc plate, and causing a gaseous film to form between the iron and the scale, thereby loosening the scale, removing the molds and rinsing drying the molds, and rubbing them with soft stone or equivalent material.

ARTHUR R. PAYNE. 

